Shear Strain Localization in Plastic Deformations

  • Athanasios E. Tzavaras
Conference paper
Part of the The IMA Volumes in Mathematics and its Applications book series (IMA, volume 52)

Abstract

Shear instabilities in the form of shear bands are often observed during high speed, plastic deformations of metals. According to one theory, their formation is attributed to effective strain-softening response, which results at high strain rates as the net outcome of the influence of thermal softening on the, normally, strain-hardening response of metals. In order to test the core instability mechanism set forth by such theories, we consider one-dimensional shear deformations of a material exhibiting strain softening and strain-rate sensitivity. The deformation is caused by either prescribed tractions or prescribed velocities. As it turns out, for moderate amounts of strain softening, strain-rate sensitivity exerts a dissipative effect and stabilizes the motion. However, once a threshold is exceeded, the response becomes unstable and shear strain localization can occur.

Keywords

Strain Hardening 

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Copyright information

© Springer-Verlag New York, Inc. 1993

Authors and Affiliations

  • Athanasios E. Tzavaras
    • 1
  1. 1.Department of MathematicsUniversity of WisconsinMadisonUSA

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